A network service provider (NSP) can operate a provider network to supply network services, for example Virtual Private Network (VPN) services, to customers. A VPN links various customer sites enabling a customer to send multimedia data between different sites transparently over a NSP network using a suitable technology, for example Multi-Protocol Label Switching (MPLS) technology. A site network includes a router, called a customer edge (CE) on the basis of positioning at the edge of the customer sites, which communicates with the provider network. The provider network can also include multiple routers, called provider edges (PEs) on the basis of positioning at the edge of the provider network, which communicates with the CEs of the VPNs.
A virtual private network (VPN) is a private communications network that is typically used within a company, or by several companies or organizations, to communicate confidentially over a publicly accessible network. VPN message traffic can be carried via a public networking infrastructure such as the Internet in addition to various standard protocols, or via a private network of a service provider in cases where a Service Level Agreement (SLA) defines an arrangement between a VPN customer and the VPN service provider.